Automatic ingot unloading device and method

ABSTRACT

A device for automatically discharging ingots from a stack of ingots is disclosed that includes a frame, a lift device positioned within the frame, a platform rotatably coupled to the lift device, and a discharge mechanism coupled to the frame. The automatic ingot discharging device of the present invention is utilized to reduce the time and labor required to move ingots from one location to another in a casting facility, and thus, increase the production efficiency for manufacturing cast objects.

FIELD OF THE INVENTION

[0001] The present invention relates generally to transport systems.More particularly, the present invention is directed to methods anddevices for automatically discharging ingots from a stack of ingots.

BACKGROUND OF THE INVENTION

[0002] In the casting industry, a metal object is created from thesolidification of molten metal in a mold that defines the shape of theobject. The metal typically arrives at a casting facility in the form ofsolid metal bars, generally referred to as ingots, that are stacked on apalette in the manner shown in FIG. 1.

[0003] Prior to formation of a metal object, the ingots have to beremoved from the stack 10 and carried to a furnace where the ingots areheated to the molten state required for injection into the mold. Where amelt system is employed at a casting facility, the ingots are,typically, placed on a conveyor; at the end of the conveyor, the ingotsfall off into a bucket; and the bucket drops the ingots into a furnacewhere the ingots are heated. As the ingots melt, the metal trickles intoa bath, where a ladle dips out an amount of the molten metal forinjection into a mold.

[0004] Shown in FIG. 1(b), is an exemplary ingot 12 that is abouttwenty-eight inches long, and approximately thirty pounds in weight. Toremove the ingots from the stack, a significant amount of manual laborand time is utilized to lift and carry the ingots from one location toanother.

[0005] Thus, the operator of the casting equipment has to stop theequipment, while ingots are being loaded, for example on the conveyor ofthe melt system. Accordingly, the production of objects is delayed.

[0006] In addition, the amount of melt in the bath varies significantlybetween drops of ingots into the furnace. During the time between dropsof metal into the melt system, the die cast parameters (i.e., theconditions required of the metal before it is deposited in a mold), suchas metal temperature, shot weight, and metal cleanliness may fluctuate.Accordingly, the die cast parameters have to be constantly monitored,and adjustments to the casting equipment have to be performed to keepthe metal within the desired die cast parameters.

[0007] Further, the exemplary ingot of FIG. 1(b) has a trapezoidalstructure. As with any trapezoidal structure, the top width 14 of thetrapezoidal structure is shorter than the bottom width 16 of thetrapezoidal structure.

[0008] Referring back to FIG. 1(a), it is shown that the top width 14 ofan ingot is smaller than the bottom width 16 of the ingot. Thus, thetops 14 of the ingots, when placed side by side, do not meet.Accordingly, after a first layer of ingots has been placed on a palettewith their bottoms 16 down, the following layer of ingots is formed byinverting the ingots, such that tops 14 of the next layer of ingots fitwithin the openings between the tops 14 of the ingots of the previouslayer (i.e., the bottoms of the ingots are at the top), and areciprocating row 18 of ingots is formed.

[0009] To form the next reciprocating stack of ingots, the ingots areusually laid perpendicular to the previous reciprocating stack, in thedirection of arrows 20. Thus, all of the ingots in a stack are notaligned in the same direction. An additional amount of manual labor andtime is needed to rotate the ingots, such that the ingots can be easilyremoved from the stack.

[0010] Accordingly, it would be desirable to provide a system and methodfor automatically unloading ingots from a stack that increases theefficiency of producing casted objects, and reduces the amount of manuallabor utilized to transport the ingots. Further, it would also bedesirable to provide a method and system for rotating the ingots, sothat the ingots are oriented in a desirable direction for removal from astack.

[0011] In addition, it would be desirable to provide a system and methodfor automatically unloading ingots that reduces the amount of monitoringof the metal in the bath, and the amount adjusting of the castingequipment to maintain the desired die cast parameters.

SUMMARY OF THE INVENTION

[0012] In one aspect of the invention, an apparatus for transferringingots from a stack of ingots is provided that includes a frame, a liftdevice positioned within the frame, a platform rotatably coupled to thelift device, and a discharge mechanism, coupled to the frame, thatpushes ingots from the stack of ingots.

[0013] In another aspect of the present invention, the platform rotatesthe stack of ingots by at least ninety degrees.

[0014] In another aspect of the present invention, a system fortransferring ingots from a stack of ingots is provided that includes ameans for lifting the stack of ingots, a means for rotating the stack ofingots, which is coupled to the rotating means, and a means fordischarging the ingots from the rotating means.

[0015] In yet another aspect of the present invention, a method isprovided for transferring ingots from a stack of ingots that includespushing a first layer of ingots from the stack of ingots, lowering thestack of ingots, rotating the stack of ingots ninety degrees, anddischarging a second layer of ingots from the stack of ingots.

[0016] There has thus been outlined, rather broadly, the more importantfeatures of the invention in order that the detailed description thereofthat follows may be better understood, and in order that the presentcontribution to the art may be better appreciated. There are, of course,additional features of the invention that will be described below andwhich will form the subject matter of the claims appended hereto.

[0017] In this respect, before explaining at least one embodiment of theinvention in detail, it is to be understood that the invention is notlimited in its application to the details of construction and to thearrangements of the components set forth in the following description orillustrated in the drawings. The invention is capable of otherembodiments and of being practiced and carried out in various ways.Also, it is to be understood that the phraseology and terminologyemployed herein, as well as the abstract, are for the purpose ofdescription and should not be regarded as limiting.

[0018] As such, those skilled in the art will appreciate that theconception upon which this disclosure is based may readily be utilizedas a basis for the designing of other structures, methods and systemsfor carrying out the several purposes of the present invention. It isimportant, therefore, that the claims be regarded as including suchequivalent constructions insofar as they do not depart from the spiritand scope of the present invention.

BRIEF DESCRIPTION OF THE FIGURES

[0019]FIG. 1(a) illustrates ingots on a palette.

[0020]FIG. 1(b) illustrates an ingot.

[0021]FIG. 2 is an automatic ingot unloading device in accordance withthe present invention.

[0022]FIG. 3 illustrates operation of an automatic ingot unloadingdevice in accordance with the present invention.

[0023]FIG. 4 is a block diagram of an automatic ingot unloading device,in accordance with the present invention, that is included in a meltsystem.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

[0024] Referring now to the figures, wherein like reference numeralsindicate like elements, in FIG. 2, there is shown an automatic transferapparatus 22 in accordance with the present invention. For purposes ofexample, the transfer apparatus 22 is described as an apparatus forlifting a stack of ingots 10, and automatically discharging the ingots16 from the stack. However, the transfer apparatus 22 of the presentinvention may be utilized for lifting and/or discharging any load.

[0025] In a preferred embodiment of the present invention, the transferapparatus 22 includes a platform 24 for positioning a palette of a stackof ingots, such as the stack of ingots 10 shown in FIG. 1(a). Theplatform 24 is rotatably coupled to a lift device 26, such that theorientation of the stack of ingots 10 is variable. In an exemplaryembodiment of the present invention, the platform 24 is stationary andthe lift device 26 rotates, such that the orientation of the stack ofitems may be varied. In another exemplary embodiment of the presentinvention, the platform rotates and the lift device 26 is stationary. Inyet another exemplary embodiment of the present invention, the platform24 and the lift device 26 rotate.

[0026] In the preferred embodiment of the present invention, the liftdevice 26 is coupled to a base 28. Alternatively, the lift device 26extends through a port or opening in the base 28.

[0027] The lift device may operate, for example via hydraulics,pneumatics, or electromechanical methods known in the art. A Pro SeriesLift and Rotate Table by PENTALIFT™ of Buffalo, N.Y. may be utilized forthe platform 24 and lift device 26.

[0028] A frame 30 is coupled to the base 28, and defines the space forinserting and positioning a stack of ingots 10. In the preferredembodiment of the present invention, the base 28 and frame 30 are madefrom a metal and welded together. However, it should be understood byone of ordinary skill in the art that the base 28 and frame 30 may beconstructed from other materials. It should also be understood by one ofordinary skill in the art that the frame 30 and/or base 28 are optional,but provide rigidity.

[0029] In the preferred embodiment of the present invention, the designof the frame 30 includes a first pair 32 of vertical members, whichincludes a front 36 and rear 38 member, connected to each other via afirst upper member 40, and a second pair 42 of vertical members, whichincludes a front 44 and rear 46 member, connected to each other via asecond upper member 48. A third upper member 50 is provided forconnecting the front members 36, 44 of each of the first and second pairof vertical members 32, 42, and a fourth upper member 52 is provided forconnecting the rear vertical members 38, 46 of each of the first andsecond pair of vertical members 32, 42.

[0030] In the preferred embodiment of the present invention, a dischargesurface 54, for example, a slide or conveyor, is coupled to the thirdupper member 50. The discharge surface may be permanently, via, forexample a welded joint, or removeably coupled to the third upper member50. It should be understood by one of ordinary skill in the art that thedischarge surface 54 is not essential to the operation of the presentinvention.

[0031] Coupled to the first upper member is a first electric motor 56that operates to push a first pushing member 58, and coupled to thesecond upper member 48 is a second electric motor 60 that operates topush a second pushing member 62.

[0032] Each of the first and second upper members 40, 48 includes agroove 64, and the first and second pushing members 58, 62 are slidablyengaged with each groove 64. In a preferred embodiment of the presentinvention, the pushing members 58, 62 are coupled to the motors via, aconnecting member, for example, a chain or cord, and the pushing members58, 62 slide within the corresponding groove by a distance correspondingto the amount of the connecting member that is released by each motor56, 60.

[0033] In another exemplary embodiment of the present invention, asingle discharge mechanism is utilized to push the ingots 16 from astack 10. Alternatively, the discharge mechanism could operate bypushing devices, for example, hydraulic or pneumatic cylinders.

[0034] The hydraulic or pneumatic pushing devices may be positioned in adirection perpendicular to the third upper member 50, and utilized topush the ingots 16, which may be positioned, for example, in a similardirection, from the stack 10. The hydraulic or pneumatic pushing devicesmay provide a sufficient amount of force to push ingots 16, which, forexample, may be shaped in a manner that does not allow the ingots 16 toeasily slide off of the underlying layer of ingots 16 onto a dischargesurface 54.

[0035] Typically, seven ingots 16 make up one layer of ingots 16. In anexemplary embodiment of the present invention, seven hydraulic orpneumatic pushing devices are positioned in a fixed location for pushingeach of the seven ingots 16 from the stack 10. In an exemplaryembodiment of the present invention, the seven ingots 16 are positionedparallel, lengthwise, to the pushing devices, and each pushing deviceindependently pushes one of the seven ingots 16 from the stack 10.

[0036] In another exemplary embodiment of the present invention, theseven ingots are positioned parallel, lengthwise, to a single pushingdevice, and the single pushing device moves along an axis perpendicularto the ingots 16 to individually push each ingot 16 form the stack 10.

[0037] In another exemplary embodiment of the present invention, theseven ingots 16 are positioned parallel, lengthwise, to a single pushingdevice that pushes, at one time, the seven ingots from the stack 10. Itshould be understood by one of ordinary skill in the art that the numberof ingots 16 per layer may vary.

[0038] During operation of the transfer apparatus 22 of the presentinvention, as shown in FIG. 3, the lift device 26 elevates a stack ofingots 10 until the first layer of the stack is positioned above thethird upper member 50, such that the ingots 16 of the first layer may bedischarged. The third upper member retains the second layer of ingots 16in their position.

[0039] The pushing means 58, 62 operate to push on the rear of the firstlayer, such that the desired number of ingots is automaticallydischarged from the stack of ingots 10 onto the discharge surface 54.

[0040] When a layer of ingots rises to the top of the stack, 10 havingingots 16 that are stacked, for example in a direction that is notparallel to the third upper member 50, the platform 24 is lowered to aposition where the frame 30 will not interfere with the rotation of thestack of ingots 10. The platform 24 is then raised again to theposition, where the pushing members 58, 62 may operate to discharge theingots 16 from the stack of ingots 10.

[0041] In another exemplary embodiment of the present invention, theplatform 24 is raised to rotate the stack of ingots 10, and then loweredto a discharging position.

[0042] In another exemplary embodiment of the present invention, wherethere is no frame 20, or where the frame 30 is designed not to interferewith the rotation of the stack of ingots 10, the platform 24 is notraised or lowered prior to rotation.

[0043] When the stack of ingots 10 includes layers that are stacked in adirection that is parallel to the first and second upper members 40, 48,the platform 24 is rotated ninety degrees to orient the stack of ingots10 in a direction that is perpendicular to the first and second uppermembers 40, 48 (and thus, parallel to the third upper member 50), toallow the first and second pushing members 58, 62 to discharge theingots 16 from the stack of ingots 10.

[0044] The transport apparatus automatically repeats the above-describedprocess of lifting, discharging and rotating the stack of ingots 10until all of the ingots 16 have been discharged form the stack 10.Accordingly, less manual labor and time is required to transport theingots 16 from one place to another.

[0045] A controller 66 is electrically coupled to the lift device 26 andthe discharge mechanism, which may be pushing members 58, 62, forexample, via the motor 56, to control the lifting and pushing operationsof the transfer system 22. The controller 66 may also be coupled to adischarge surface 54, such as an electromechanical conveyor, toautomatically control the rate at which the ingots 16 move along theconveyor. The controller 66 may be electrically coupled to the transfersystem 22 via conductive devices or radio frequency methods.

[0046] Shown in FIG. 4, the transfer system 22 of the present inventionis part of a melt system 68. The melt system 68 includes the transferapparatus 22, with or without the discharge apparatus 54, a conveyor 70,a bucket 72, a furnace 74 and a bath 76. When the transfer apparatus 22is placed in the melt system 68, the casting machines do not have to bestopped to load ingots 16 onto the conveyor 70 of the melt system 68.Accordingly, more objects can be manufactured in a certain time frame,and the production of objects is more efficient.

[0047] Further, there is a continuous deposit of metal into the bath 76.Accordingly, a constant level of molten metal can be maintained for themaking of objects. In addition, the die parameters do not significantlyvary because the time frame, during which the die parameters couldfluctuate, is reduced. Accordingly, the die parameters of the metal canbe monitored less, and the adjusting of the casting machinery tomaintain the die parameters may also be less.

[0048] The many features and advantages of the invention are apparentfrom the detailed specification, and thus, it is intended by theappended claims to cover all such features and advantages of theinvention which fall within the true spirit and scope of the invention.Further, since numerous modifications and variations will readily occurto those skilled in the art, it is not desired to limit the invention tothe exact construction and operation illustrated and described, andaccordingly, all suitable modifications and equivalents may be resortedto as falling within the scope of the invention.

What is claimed:
 1. An apparatus for transferring ingots from a stack ofingots, comprising: a frame; a lift device positioned within the frame;a platform rotatably coupled to the lift device; and a dischargemechanism that pushes the ingots from the stack of ingots, saiddischarge mechanism coupled to the frame.
 2. The apparatus of claim 1,where the platform is configured to rotate ninety degrees clockwise orcounterclockwise.
 3. The apparatus of claim 1, further comprising: abase coupled to the frame.
 4. The apparatus of claim 3, wherein the liftdevice is coupled to the base.
 5. The apparatus of claim 1, furthercomprising a first motor coupled to the discharge mechanism.
 6. Theapparatus of claim 6, further comprising a connecting member coupledbetween the motor and the discharge mechanism.
 7. The apparatus of claim1, wherein the discharge mechanism is at least one of a hydraulicdischarge mechanism and a pneumatic discharge mechanism.
 8. Theapparatus of claim 1, wherein the lift device is at least one of ahydraulic lift device, and a pneumatic lift device.
 9. The apparatus ofclaim 1, wherein the frame comprises: a first pair of vertical membersconnected via a first upper member; and a second pair of verticalmembers connected via a second upper member.
 10. The apparatus of claim9, wherein the first pair of vertical members comprises: a first frontvertical member; and a first rear vertical member, and wherein thesecond pair of vertical members comprises: a second front verticalmember; and a second rear vertical member.
 11. The apparatus of claim10, wherein the first upper member includes a first groove, and thesecond upper member includes a second groove.
 12. The apparatus of claim11, wherein the discharge mechanism is slidably positioned between thefirst groove and second groove.
 13. The apparatus of claim 11, whereinthe discharge mechanism comprises: a first pushing member; and a secondpushing member.
 14. The apparatus of claim 13, wherein the first pushingmember is slidably positioned within the first groove and the secondpushing member is slidably positioned within the second groove.
 15. Theapparatus of claim 1, further comprising: a discharge surface coupled tothe frame.
 16. The apparatus of claim 15, wherein the discharge surfaceis at least one of a slide and a conveyor.
 17. A system for transferringingots from a stack of ingots, comprising: means for lifting the stackof ingots; means for rotating the stack of ingots, said rotating meanscoupled to the lifting means; and means or discharging the ingots fromthe rotating means.
 18. The apparatus of claim 17, wherein the rotatingmeans rotates the ingots by ninety degrees.
 19. A method fortransferring ingots from a stack of ingots, comprising: dischargingingots from a first a layer of ingots in the stack of ingots; rotatingthe stack of ingots ninety degrees; and discharging the ingots from asecond layer of ingots of the stack of ingots.
 20. The method of claim19, further comprising: lowering the stack of ingots after dischargingthe first layer of ingots; and raising the stack of ingots beforedischarging the ingots from the second layer of ingots.
 21. Theapparatus of claim 1, wherein the discharge mechanism comprises sevenpushing members.